Water Supply and Sanitation in Bangladesh - Water Resources - Arsenic Contamination of Groundwater

Arsenic Contamination of Groundwater

In 1993 it was discovered that groundwater in large parts of Bangladesh was naturally contaminated with arsenic. The World Health Organization (WHO) estimated in 2000 that between 35 and 77 million of the 125 million Bangladeshis were at risk of drinking contaminated water. In an interview published by the WHO in 2008, Professor Mahmuder Rahman quoted government estimates saying that up to 70 million people still drink water which exceeds the WHO guidelines of 10 micrograms per liter of arsenic, and 30 million drink water containing more than the Bangladesh National Standard of 50 micrograms per liter. Alternative sources of water are deep-tube wells that pump uncontaminated groundwater, surface water, rainwater harvesting and pond sand filters. According to the 2006 Multiple Indicator Cluster Survey, just over half of the people surveyed (55 per cent) indicated that they use arsenic-free tube wells, 21 per cent reported using boiled surface water (from canals, ponds and rivers), 5 per cent rely on rainwater and 2.4 per cent use pond sand filters. The UN Rapporteur on the human right to water and sanitation was told in 2009 that the main government strategy to provide alternative water sources were deep tube wells, not increased use of surface water, as stated in the 2004 government strategy. The government sells four types of household-level arsenic filters through a "Deployment of Arsenic Removal Technologies" (DART) Programme supported by CIDA. The four filters are the Sono arsenic filter, the Alcan Enhanced Activated Alumina filter, the Bangladesh University of Engineering and Technology (BUET) Activated Alumina filter and the Stevens Institute of Technology filter. Until 2008, nearly 18,000 household filters and 50 community filters have been installed under the DART programme alone. Through the programme, individuals can buy the filters for between 3,500 and 5,000 takas (USD 50-70). For the very poorest, the filters are available at 10 per cent of the full price. Nevertheless, some people cannot afford filters and continue to drink arsenic-contaminated water. Other programs distribute filters for free. For example, of 32,500 Sono filters installed until 2008, two thirds were distributed for free.